Same field on different pages

[Laurent GARNIER]

Hello, I have a group of pages based on different termplates, but they all have the same header. In the header of these page, I have a scrolling text. I would like this scrolling text (which is a bigtext field) to be the same on all the pages. When I change the scrolling text on one page, I would like the modification to take effect on all pages. Is there a way to do this?   Thank you. Laurent